R: Utility Functions for Delay Differential Equation Systems

dde.utils {scaRabee}

R Documentation

Utility Functions for Delay Differential Equation Systems

Description

This is a collection of utility functions called by dde.model when a model defined by delay differential equations is evaluated. None of these functions is typically called directly by users.

Usage

  dde.syst(t = NULL,
           y = NULL,
           ic = NULL,
           parms = NULL,
           derparms = NULL,
           delags = NULL,
           codedde = NULL,
           dosing = NULL,
           has.dosing = NULL,
           dose.states = NULL,
           xdata = NULL,
           covdata = NULL,
           scale = NULL,
           check = FALSE)
  dde.lags(parms = NULL,
           derparms = NULL,
           codelags = NULL,
           check = FALSE)

Arguments

`t`	A scalar or a vector of numerical time values.
`y`	A vector of system state values.
`ic`	A vector of initial conditions, typically returned by `init.cond`.
`parms`	A vector of primary parameters.
`derparms`	A list of derived parameters, specified in the $DERIVED block of code.
`delags`	A vector of delay parameters, typically returned by `dde.lags`.
`codedde`	The content of the R code specified within the $DDE block in the model file.
`dosing`	A data.frame of dosing information created by `make.dosing` from instantaneous and zero-order inputs into the system and containing the following columns: TIME Dosing event times. CMT State where the input should be assigned to. AMT Amount that should be assigned to system `state` at the corresponding `TIME`. RATE Rate of input that should be assigned to system `CMT` at the corresponding `TIME`. See `vignette('scaRabee',package='scaRabee')` for more details about the interpolation of the input rate at time not specified in `dosing`. TYPE An indicator of the type of input. `TYPE` is set to 1 if the record in `dosing` correspond an original bolus input; it is set to 0 otherwise.
`has.dosing`	A logical variable, indicating whether any input has to be assigned to a system state.
`dose.states`	A vector of integers, indicating in which system state one or more doses have to be assigned to.
`xdata`	A vector of times at which the system is being evaluated.
`covdata`	A matrix of covariate data extracted from the dataset.
`scale`	A vector of system scale, typically returned by `input.scaling`
`check`	An indicator whether checks should be performed to validate function inputs
`codelags`	The content of the R code specified within the $LAGS block in the model file.

Details

dde.syst is the function which actually evaluates the system of delay differential equations specified in the $DDE block.

dde.lags is the function which evaluates the code specified in the $LAG block and defines the delays at which the system needs to be computed.

Author(s)